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Cosintering (La0.84Sr0.16MnO3 thin‐film cathode/ZrO2: 8 mol% Y2O3 thin‐film solid electrolyte/55 vol.% ZrO2:8 mol% Y2O3 + 45 vol.% NiO anode, ϕ = 12 × 1.5 mm thick pellet) was achieved by applying an electric field for 5 min at 1200°C. Impedance spectroscopy measurements of the anode‐supported three‐layer cell show an improvement of the electrical conductivity in comparison to that of a conventionally sintered cell. The scanning electron microscopy images of the cross‐sections of electric field‐assisted pressureless sintered cells show a fairly dense electrolyte and porous anode and cathode. Joule heating, resulting from the electric current due to the application of the AC electric field, is suggested as responsible for sintering. Dilatometric shrinkage curves, electric voltage and current profiles, impedance spectroscopy diagrams, and scanning electron microscopy micrographs show how anode‐electrolyte‐cathode ceramic cells can be cosintered at temperatures lower than the usually required. [ABSTRACT FROM AUTHOR]

Electromechanical metal oxides, such as piezoceramics, are often incompatible with soft polymers due to their crystallinity requirements, leading to high processing temperatures. This study explores the potential of ceria-based thin films as electromechanical actuators for flexible electronics. Oxygen-deficient fluorites, like cerium oxide, are centrosymmetric nonpiezoelectric crystalline metal oxides that demonstrate giant electrostriction. These films, deposited at low temperatures, integrate seamlessly with various soft substrates like polyimide and PET. Ceria thin films exhibit remarkable electrostriction (M33 > 10-16 m² V-2) and inverse pseudo-piezo coefficients (e33 > 500 pmV-1), enabling large displacements in soft electromechanical systems. Our study explores resonant and off-resonant configurations in the low-frequency regime (<1 kHz), demonstrating versatility for three-dimensional and transparent electronics. This work advances the understanding of oxygen-defective metal oxide electromechanical properties and paves the way for developing versatile and efficient electromechanical systems for applications in biomedical devices, optical devices, and beyond. [ABSTRACT FROM AUTHOR]

Direct conversion of methane to C 2 compounds by oxidative and nonoxidative coupling reactions has been intensively studied in the past four decades; however, because these reactions have intrinsic severe thermodynamic constraints, they have not become viable industrially. Recently, with the increasing availability of inexpensive "green electrons" coming from renewable sources, electrochemical technologies are gaining momentum for reactions that have been challenging for more conventional catalysis. Using solid-state membranes to control the reacting species and separate products in a single step is a crucial advantage. Devices using ionic or mixed ionic-electronic conductors can be explored for methane coupling reactions with great potential to increase selectivity. Although these technologies are still in the early scaling stages, they offer a sustainable path for the utilization of methane and benefit from the advances in both solid oxide fuel cells and electrolyzers. This review identifies promising developments for solid-state methane conversion reactors by assessing multifunctional layers with microstructural control; combining solid electrolytes (proton and oxygen ion conductors) with active and selective electrodes/catalysts; applying more efficient reactor designs; understanding the reaction/degradation mechanisms; defining standards for performance evaluation; and carrying techno-economic analysis.